Exemple #1
0
SEXP dbExistsTable(SEXP dbi_conn_sexp, SEXP tableName_sexp) {
  SEXP ans;

 if(TYPEOF(dbi_conn_sexp) != EXTPTRSXP || dbi_conn_sexp == R_NilValue) {
    return R_NilValue;
  }

  DatabaseConnection* conn = reinterpret_cast<DatabaseConnection*>(R_ExternalPtrAddr(dbi_conn_sexp));
  if(!conn) {
    // throw bad_connection_object
    REprintf("bad database connection.\n");
    return R_NilValue;
  }

  const char* tableName = CHAR(STRING_ELT(tableName_sexp,0));
  PROTECT(ans = allocVector(LGLSXP,1));
  LOGICAL(ans)[0] = static_cast<int>(conn->existsTable(tableName));
  UNPROTECT(1);
  return ans;
}
Exemple #2
0
// return number of rows written to database
// using both overwrite and append is a bad design decision
// there should just be overwrite, which will drop the table if it exists
// append should be automatic if the table exists, and should fail if the row formats don't match up
// having both overwrite and append just complicates the logic of this function
SEXP dbWriteTable(SEXP dbi_conn_sexp, SEXP tableName_sexp, SEXP value_sexp, SEXP writeRowNames_sexp, SEXP overWrite_sexp, SEXP append_sexp) {
  SEXP ans;
  int rows;

 if(TYPEOF(dbi_conn_sexp) != EXTPTRSXP || dbi_conn_sexp == R_NilValue) {
    return R_NilValue;
  }

  DatabaseConnection* conn = reinterpret_cast<DatabaseConnection*>(R_ExternalPtrAddr(dbi_conn_sexp));
  if(!conn) {
    // throw bad_connection_object
    REprintf("bad database connection.\n");
    return ScalarInteger(0);
  }
  if(TYPEOF(tableName_sexp) != STRSXP) {
    REprintf("ERROR: tableName is not a string.\n");
    return ScalarInteger(0);
  }
  const char* tableName = CHAR(STRING_ELT(tableName_sexp,0));
  const bool writeRowNames = static_cast<bool>(LOGICAL(writeRowNames_sexp)[0]);
  const bool overWrite = static_cast<bool>(LOGICAL(overWrite_sexp)[0]);

  if(conn->existsTable(tableName) && overWrite) {
    if(!conn->removeTable(tableName)) {
      REprintf("could not remove existing table (aborting).\n");
      return ScalarInteger(0);
    }
  }

  try {
    rows = conn->writeTable(tableName, value_sexp, writeRowNames);
  } catch (MapToTypeNotImplemented& e) {
    REprintf("%s\n",e.what());
    return R_NilValue;
  }
  PROTECT(ans = allocVector(INTSXP,1));
  INTEGER(ans)[0] = rows;
  UNPROTECT(1);
  return ans;
}